Friday the 13th Part II (1981)
Two months following the massacre at Camp Crystal Lake in the original film, Alice L. Hardy is trying to put her life together again. While feeding her cat, she discovers the severed head of Pamela Voorhees in her refrigerator before an unknown killer (whose face isn't shown) inserts an ice pick in her skull and kills her. Five years later, a man named Jeff, his girlfriend, Sandra, and Jeff's friend, Ted, are on their way to a counselor training center that is opening up at Crystal Lake, not far from the infamous campground. Despite its infamy and the police frowning on the location, Paul collects a group of would-be counselors to train. Even with warnings from local oddball Crazy Ralph, the other counselors continue to arrive, including good girls Terry and Vicki, prankster Scott, and wheelchair-bound Mark. Paul's girlfriend and assistant, Ginny Field, arrives late, much to his chagrin. As the day progresses, inspired by the legend of Jason Voorhees whose story was told at a campfire the night before, Sandra and Jeff sneak over to explore the abandoned camp, only to be caught by the sheriff (not knowing that Crazy Ralph was just strangled with a strip of barbwire by an unseen killer). After leaving them in Paul's care, the sheriff sees someone (who appears to be masked) running through the woods. He chases after him to a dilapidated shack where the sheriff makes a particularly gruesome discovery (unseen to the viewer) before someone sneaks up behind him and rams the claw side of a hammer into his skull, killing him. That night, Paul and Ginny take the counselors for one last night on the town; Sandra and Jeff, being punished for their excursion earlier, are volunteered to stay behind; Terry decides to stay behind and look for her missing dog, Muffin; while Scott volunteers to put the moves on Terry. Wheelchair-bound Mark decides to stay as well; Vicki, smitten with Mark, decides to stay. While searching for Muffin, Terry goes skinny dipping and Scott plays a prank on her by stealing her clothes before being caught in one of Paul's survival traps. Terry goes to get a knife to cut him down, but the killer slits his throat with a machete and kills Terry (off screen) when she returns and discovers him dead. At the bar, Ginny imagines what Jason would be like if he were alive, deducing he had seen his mother murdered and would be a vengeful creature unaware of the meaning of life and death. Paul dismisses her concerns and tells her that he is only a legend. As it begins raining heavily back at the camp, the killer murders Mark with a machete to the face. He then moves upstairs and kills Jeff and Sandra as they are having sex by double impalement with a spear. When Vicki returns for Mark, she is attacked by the killer, who is revealed to be wearing a gunny sack over his head with an eye hole cut out. He corners Vicki and stabs her in the stomach with a kitchen knife, killing her. Paul and Ginny return from town to discover the aftermath. Paul is attacked by the killer, who then chases Ginny through the camp. She accidentally finds her way to the killer's shack and enters to find an altar with Mrs. Voorhees' mummified head on it, surrounded by the bodies of the recent victims. At this point, Ginny realizes that Jason is the true killer, seeking revenge for his mother's death. Using her study of child psychology to her advantage, she puts on Pamela's sweater and manages to convince Jason that she is his mother. The ruse fails when he eventually spots his mother's head, but Paul intervenes, distracting Jason long enough for Ginny to take the machete and bring it down several inches into his shoulder. Jason falls over, presumably dead. Ginny and Paul uncover his disfigured face (unseen to the viewer) before taking shelter in a nearby cabin. Muffin then appears at the cabin door, and while Ginny reaches down to pick her up, Jason (now unmasked, with the machete still in his shoulder) bursts through the window behind her and attacks her. Ginny wakes up the next morning, confused and being pulled aboard an ambulance with no recollection of how she escaped. She calls for Paul, who is nowhere to be seen, and she is driven off to the hospital. The final scene then switches over to show Mrs. Voorhees' head, before ultimately fading to black.